SSD/Linux have BSD-style base system and additional softwares will be
installed with pkgsrc.
On the other hand, Debian GNU/kFreeBSD is ....

I heard about Debian porting their system to FreeBSD and NetBSD kernels; they
even have ready an early release of their Debian-FreeBSD.
Are you sure you typed SSD/Linux correctly? I couldn't find it through
distrowatch.com, and Google search had links for Linux on solid-state drives,
but not a Linux distribution by that name.